The clinical and molecular cardiometabolic fingerprint of an exploratory psoriatic arthritis cohort is associated with the disease activity and differentially modulated by methotrexate and apremilast.

OBJECTIVES: (1) To evaluate clinical and molecular cardiovascular disease (CVD) signs and their relationship with psoriatic arthritis (PsA) features and (2) to identify a clinical patient profile susceptible to benefit from methotrexate (MTX) and/or apremilast regarding CVD risk. METHODS: This cross-sectional study included 100 patients with PsA and 100 age-matched healthy donors. In addition, an exploratory cohort of 45 biologically naïve patients treated for 6 months with apremilast, MTX or combined therapy according to routine clinical practice was recruited. Extensive clinical and metabolic profiles were obtained. Ninety-nine surrogate CVD-related molecules were analysed in plasma and peripheral blood mononuclear cells (PBMCs). Hard cluster analysis was performed to identify the clinical and molecular phenotypes. Mechanistic studies were performed on adipocytes. RESULTS: Cardiometabolic comorbidities were associated with disease activity and long-term inflammatory status. Thirty-five CVD-related proteins were altered in the plasma and PBMCs of PsA patients and were associated with the key clinical features of the disease. Plasma levels of some of the CVD-related molecules might distinguish insulin-resistant patients (MMP-3, CD163, FABP-4), high disease activity (GAL-3 and FABP-4) and poor therapy outcomes (CD-163, LTBR and CNTN-1). Hard cluster analysis identified two phenotypes of patients according to the rates of cardiometabolic comorbidities with distinctive clinical and molecular responses to each treatment. CONCLUSIONS: (1) Novel CVD-related proteins associated with clinical features could be emerging therapeutic targets in the context of PsA and (2) the pleiotropic action of apremilast could make it an excellent choice for the management of PsA patients with high CVD risk, targeting metabolic alterations and CVD-related molecules.

Splicing machinery is impaired in rheumatoid arthritis, associated with disease activity and modulated by anti-TNF therapy.

OBJECTIVES: To characterise splicing machinery (SM) alterations in leucocytes of patients with rheumatoid arthritis (RA), and to assess its influence on their clinical profile and therapeutic response. METHODS: Leucocyte subtypes from 129 patients with RA and 29 healthy donors (HD) were purified, and 45 selected SM elements (SME) were evaluated by quantitative PCR-array based on microfluidic technology (Fluidigm). Modulation by anti-tumour necrosis factor (TNF) therapy and underlying regulatory mechanisms were assessed. RESULTS: An altered expression of several SME was found in RA leucocytes. Eight elements (SNRNP70, SNRNP200, U2AF2, RNU4ATAC, RBM3, RBM17, KHDRBS1 and SRSF10) were equally altered in all leucocytes subtypes. Logistic regressions revealed that this signature might: discriminate RA and HD, and anti-citrullinated protein antibodies (ACPAs) positivity; classify high-disease activity (disease activity score-28 (DAS28) >5.1); recognise radiological involvement; and identify patients showing atheroma plaques. Furthermore, this signature was altered in RA synovial fluid and ankle joints of K/BxN-arthritic mice. An available RNA-seq data set enabled to validate data and identified distinctive splicing events and splicing variants among patients with RA expressing high and low SME levels. 3 and 6 months anti-TNF therapy reversed their expression in parallel to the reduction of the inflammatory profile. In vitro, ACPAs modulated SME, at least partially, by Fc Receptor (FcR)-dependent mechanisms. Key inflammatory cytokines further altered SME. Lastly, induced SNRNP70-overexpression and KHDRBS1-overexpression reversed inflammation in lymphocytes, NETosis in neutrophils and adhesion in RA monocytes and influenced activity of RA synovial fibroblasts. CONCLUSIONS: Overall, we have characterised for the first time a signature comprising eight dysregulated SME in RA leucocytes from both peripheral blood and synovial fluid, linked to disease pathophysiology, modulated by ACPAs and reversed by anti-TNF therapy.

Anti-dsDNA Antibodies Increase the Cardiovascular Risk in Systemic Lupus Erythematosus Promoting a Distinctive Immune and Vascular Activation.

Objective: Systemic lupus erythematosus (SLE) is associated to boosted atherosclerosis development and a higher cardiovascular disease risk. This study aimed to delineate the role of anti-double stranded DNA (anti-dsDNA) antibodies on the molecular profile and the activity of immune and vascular cells, as well as on their enhanced cardiovascular risk. Approach and Results: Eighty SLE patients were included. Extensive clinical/analytical evaluation was performed, including cardiovascular disease parameters (endothelial function, proatherogenic dyslipidemia, and carotid intima-media thickness). Gene and protein expression profiles were evaluated in monocytes from patients diagnosed positive or negative for anti-dsDNA antibodies by using NanoString and cytokine arrays, respectively. NETosis and circulating inflammatory profile was assessed in both neutrophils and plasma. Positivity and persistence of anti-dsDNA antibodies in SLE patients were associated to endothelial dysfunction, proatherogenic dyslipidemia, and accelerated atherosclerosis. In parallel, anti-dsDNA antibodies were linked to the aberrant activation of innate immune cells, so that anti-dsDNA(+) SLE monocytes showed distinctive gene and protein expression/activity profiles, and neutrophils were more prone to suffer NETosis in comparison with anti-dsDNA(−) patients. Anti-dsDNA(+) patients further displayed altered levels of numerous circulating mediators related to inflammation, NETosis, and cardiovascular risk. In vitro, Ig-dsDNA promoted NETosis on neutrophils, apoptosis on monocytes, modulated the expression of inflammation and thrombosis-related molecules, and induced endothelial activation, at least partially, by FcR (Fc receptor)-binding mechanisms. Conclusions: Anti-dsDNA antibodies increase the cardiovascular risk of SLE patients by altering key molecular processes that drive a distinctive and coordinated immune and vascular activation, representing a potential tool in the management of this comorbidity.

Expression of DDX11 and DNM1L at the 12p11 Locus Modulates Systemic Lupus Erythematosus Susceptibility.

OBJECTIVES: This study employed genetic and functional analyses using OASIS meta-analysis of multiple existing GWAS and gene-expression datasets to identify novel SLE genes. METHODS: Four hundred and ten genes were mapped using SNIPPER to 30 SLE GWAS loci and investigated for expression in three SLE GEO-datasets and the Cordoba GSE50395-dataset. Blood eQTL for significant SNPs in SLE loci and STRING for functional pathways of differentially expressed genes were used. Confirmatory qPCR on SLE monocytes was performed. The entire 12p11 locus was investigated for genetic association using two additional GWAS. Expression of 150 genes at this locus was assessed. Based on this significance, qPCRs for DNM1L and KRAS were performed. RESULTS: Fifty genes were differentially expressed in at least two SLE GEO-datasets, with all probes directionally aligned. DDX11, an RNA helicase involved in genome stability, was downregulated in both GEO and Cordoba datasets. The most significant SNP, rs3741869 in OASIS locus 12p11.21, containing DDX11, was a cis-eQTL regulating DDX11 expression. DDX11 was found repressed. The entire 12p11 locus showed three association peaks. Gene expression in GEO datasets identified DNM1L and KRAS, besides DDX11. Confirmatory qPCR validated DNM1L as an SLE susceptibility gene. DDX11, DNM1L and KRAS interact with each other and multiple known SLE genes including STAT1/STAT4 and major components of IFN-dependent gene expression, and are responsible for signal transduction of cytokines, hormones, and growth-factors, deregulation of which is involved in SLE-development. CONCLUSION: A genomic convergence approach with OASIS analysis of multiple GWAS and expression datasets identified DDX11 and DNM1L as novel SLE-genes, the expression of which is altered in monocytes from SLE patients. This study lays the foundation for understanding the pathogenic involvement of DDX11 and DNM1L in SLE by identifying them using a systems-biology approach, while the 12p11 locus harboring these genes was previously missed by four independent GWAS.

Molecular Changes in the Adipose Tissue Induced by Rheumatoid Arthritis: Effects of Disease-Modifying Anti-Rheumatic Drugs.

Disease severity, progression and response to therapy might be worse in obese rheumatoid arthritis (RA) patients, but paradoxically, obesity also might protect from radiographic joint damage. Thus, the intricate relationship between obesity and RA needs urgent clarification. The aim of this study was to assess the influence of obesity on the onset and development of RA and to determine whether arthritis could modify the adipose tissue biology and whether conventional Disease Modifying Anti-Rheumatic Drugs (cDMARDs) can modulate these alterations. Two strategies were followed: (1) clinical profiling of two cohorts of RA: non-obese and obese patients; and (2) mechanistic studies carried out in both a collagen-induced arthritis (CIA) in an obese mouse model and 3T3-L1 adipocytes treated with cDMARDs (leflunomide, methotrexate, and hydroxychloroquine). In our cohort of RA patients with low-moderate disease activity, the presence of obesity was not related to a higher activity of the disease; actually, disease activity score 28-erythrocyte sedimentation rate (DAS28-ESR) was reduced in the obese RA patients. However, the induction of arthritis promoted transcriptomic changes in the adipose tissue under obesity condition in the obese CIA model. Treatment with hydroxychloroquine reduced weight and insulin resistance, accompanied by beneficial metabolic effects in the adipose tissue. These molecular changes in adipose tissue were also observed after methotrexate administration. In sum, arthritis might affect directly the inflammatory burden and metabolic alterations associated with obesity in adipose tissue. Clinicians should be cautious measuring the activity of the disease in obesity and managing the best therapeutic options for the metabolic comorbidities of these patients, where the combination of hydroxychloroquine and methotrexate should be considered to improve adipose tissue dysfunction in obese RA.

Molecular Characterization of Monocyte Subsets Reveals Specific and Distinctive Molecular Signatures Associated With Cardiovascular Disease in Rheumatoid Arthritis.

Objectives: This study, developed within the Innovative Medicines Initiative Joint Undertaking project PRECISESADS framework, aimed at functionally characterize the monocyte subsets in RA patients, and analyze their involvement in the increased CV risk associated with RA. Methods: The frequencies of monocyte subpopulations in the peripheral blood of 140 RA patients and 145 healthy donors (HDs) included in the PRECISESADS study were determined by flow cytometry. A second cohort of 50 RA patients and 30 HDs was included, of which CD14+ and CD16+ monocyte subpopulations were isolated using immuno-magnetic selection. Their transcriptomic profiles (mRNA and microRNA), proinflammatory patterns and activated pathways were evaluated and related to clinical features and CV risk. Mechanistic in vitro analyses were further performed. Results: CD14++CD16+ intermediate monocytes were extended in both cohorts of RA patients. Their increased frequency was associated with the positivity for autoantibodies, disease duration, inflammation, endothelial dysfunction and the presence of atheroma plaques, as well as with the CV risk score. CD14+ and CD16+ monocyte subsets showed distinctive and specific mRNA and microRNA profiles, along with specific intracellular signaling activation, indicating different functionalities. Moreover, that specific molecular profiles were interrelated and associated to atherosclerosis development and increased CV risk in RA patients. In vitro, RA serum promoted differentiation of CD14+CD16- to CD14++CD16+ monocytes. Co-culture with RA-isolated monocyte subsets induced differential activation of endothelial cells. Conclusions: Our overall data suggest that the generation of inflammatory monocytes is associated to the autoimmune/inflammatory response that mediates RA. These monocyte subsets, -which display specific and distinctive molecular signatures- might promote endothelial dysfunction and in turn, the progression of atherosclerosis through a finely regulated process driving CVD development in RA.